Myopia, also termed "nearsightedness," afflicts more than 70 million people in North America. The condition is characterized by the ability to see nearby objects clearly while distant objects appear blurry. Myopia starts to occur in people between the ages of eight and twelve and almost always before the age of twenty. It typically stabilizes in adulthood.
Presbyopia, a condition that occurs naturally in the aging process, is characterized by the lenses of the human eye losing their elasticity and consequently their ability to focus or accommodate for focused vision of objects located relatively close to the eye, such as reading a newspaper or a computer screen, for example. However, typically, myopic persons are able to view close objects in focus without the need for corrective lenses. Presbyopia usually occurs between ages forty and fifty.
Usually worn after the onset of presbyopia as people approach their mid-forties, bifocal lenses are one means for correcting the vision of people having myopia and presbyopia. In the bifocal lens eyeglasses, the top portion corrects the vision to allow for clear viewing at a distance and the bottom portion corrects vision to provide viewing of objects that are nearby. However, bifocal lenses are relatively expensive and require a user to view close objects through the lens.
Consequently, there exists a need for specialized eyeglasses for individuals who suffer from myopia and presbyopia that readily permit viewing of distant and close objects without the necessity of bifocal eyeglasses and the inherent limitations of such eyeglasses.